// ThisParameterType<Type>
    // 提取函数类型的this参数的类型,如果函数类型中没注明this的类型，那么返回unknown
    function toHex(this: Number) {
        return this.toString(16);
      }
       
      function numberToString(n: ThisParameterType<typeof toHex>) {
        return toHex.apply(n);
      }

      function toHex1() {
        return this.toString(16);
      }
      type dadas = ThisParameterType<typeof toHex1>
      export {}
      type thisParameterType<T extends (...arg:any)=>any> = T extends ( this:infer H,...arg:any)=>any? H :never
      const das = ()=>{}
      type fdads = thisParameterType<typeof das>